The Canon ef 100mm macro lens

I've bought a Canon EF100mm macro lens. Many review sites praised it for
sharpness and colour. I have compared it with my 24-105mm f4L on extension
tubes and it seems to be lacking colour saturation and sharpness. (On my
350D)

So what am I doing wrong? I used a very small apeture and a very firm
tripod, shot in RAW and converted to TIFF. This would seem to offer the
lenses their best chance of performing well.

Is the 100mm macro less good than an L series zoom on extension tubes? I do
admire the L series lens but would have thought that a dedicated macro lens
may have matched it when it was used for its intended purpose and the L lens
was pressed into use by adding tubes.

Advertisements

"Eatmorepies" <> a écrit dans le message de news: ...
> I've bought a Canon EF100mm macro lens. Many review sites praised it for
> sharpness and colour. I have compared it with my 24-105mm f4L on extension
> tubes and it seems to be lacking colour saturation and sharpness. (On my
> 350D)
>
> So what am I doing wrong?
>
> John
>

Maybe a too smal aperture degrades constrast, or induces some difraction, or
is not the optimal aperture for the specific lens (it is not uncommon that
f:5,6 or f:8 gives a lens its top efficiency in definition or contrast).
Did you use both lenses with a similar aperture?
(Just trying to guess...)

Advertisements

Eatmorepies wrote:
> I've bought a Canon EF100mm macro lens. Many review sites praised it
> for sharpness and colour. I have compared it with my 24-105mm f4L on
> extension tubes and it seems to be lacking colour saturation and
> sharpness. (On my 350D)
>
> So what am I doing wrong? I used a very small apeture and a very firm
> tripod, shot in RAW and converted to TIFF. This would seem to offer
> the lenses their best chance of performing well.
>
> Is the 100mm macro less good than an L series zoom on extension
> tubes? I do admire the L series lens but would have thought that a
> dedicated macro lens may have matched it when it was used for its
> intended purpose and the L lens was pressed into use by adding tubes.
>
> John

most lens are sharpest at about the mid point of the aperture range.
Smaller aperture does not sharpen an lens, but rather it increases the DOF
so sometimes I may look sharper. Most Macros have smaller apertures
available than similar general purpose lenses because DOF is sometimes a
problem for close work.

"Eatmorepies" <> wrote in
news::
> I've bought a Canon EF100mm macro lens. Many review sites praised it
> for sharpness and colour. I have compared it with my 24-105mm f4L on
> extension tubes and it seems to be lacking colour saturation and
> sharpness. (On my 350D)

I've also noticed discrepancies between the real world performances of my
lenses and the theoretical, reported performance...

Here are the MTF curves for both lenses. In theory, for sharpness the 100mm
should be a bit better, although the 24-105 is a very good lens.

Eatmorepies wrote:
> I've bought a Canon EF100mm macro lens. Many review sites praised it for
> sharpness and colour. I have compared it with my 24-105mm f4L on extension
> tubes and it seems to be lacking colour saturation and sharpness. (On my
> 350D)
>
> So what am I doing wrong? I used a very small apeture and a very firm
> tripod, shot in RAW and converted to TIFF. This would seem to offer the
> lenses their best chance of performing well.
>
> Is the 100mm macro less good than an L series zoom on extension tubes? I do
> admire the L series lens but would have thought that a dedicated macro lens
> may have matched it when it was used for its intended purpose and the L lens
> was pressed into use by adding tubes.
>
> John

> Eatmorepies writes ...
>
>I've bought a Canon EF100mm macro lens. Many review sites
>praised it for sharpness and colour. I have compared it with my
>24-105mm f4L on extension tubes and it seems to be lacking
>colour saturation and sharpness

I have both of these lenses and I'm surprised at what you just wrote
.... the 100 f/2.8 macro is a very good lens. I haven't tested then
side-by-side as competing close-up solutions, but I did use the 24-105
f/4L as a 'macro' lens in early April while in Holland (couldn't bring
the macro due to space issues) and I wasn't all that impressed by it.
Can you post a couple of pics showing the differences you're seeing?
> Is the 100mm macro less good than an L series zoom on
> extension tubes?

The fixed focal length L lenses are optically superb and the MTF curves
of the best (300 f/2.8, 500 f/4, 400 f/2.8 IS lenses for example) are
all better than the 100 f/2.8 ... but zooms are a different matter ...
the Lens Work book I have doesn't show the 24-105 MTF curves but in
that book the 100 f/2.8 curves are better than the 70-200 f/2.8 L IS
and 100-400 L IS lenses at 70 and 100 mm, which is what I'd expect
given the compromises in a 3:1 and 4:1 zoom ... I seriously doubt the
24-105 f/4 L is as good as the 70-200 f/2.8 L IS optically.

If I can find some time I'll maybe shoot a Gretag ColorChecker chart
with my 100 macro and the 24-105 @ 100 and compare ...

>
> Jeez, the curves for the 24-105 at f/4 are awful! As an owner of the
> lens I wish I had never seen these
>
> Bill
>

I was using very small apetures with both the 100mm f2.8 and the 24-105mm
f4L.

Interesting that you report that the L lens at f4 has poor curves. I find it
to be excellent on my 350D - am I going to be disappointed when I summon up
the courage to lash out for a full frame digital body?

>> I wrote ...
>>
>> Jeez, the curves for the 24-105 at f/4 are awful! As an owner of the
>> lens I wish I had never seen these
>Eatmorepies wrote ...
>
>Interesting that you report that the L lens at f4 has poor curves. I find it
>to be excellent on my 350D - am I going to be disappointed when I summon
>up the courage to lash out for a full frame digital body?

On my 'digital for africa' web page I have a couple of MTF charts
showing why a marginal lens like the 100-400 L IS is OK for cameras
like the 350 D but disappointing wide open with full frame ...
basically you are avoiding the worst of the contrast loss (which shows
up as vignetting) by using a 1.6x sensor ...http://members.aol.com/bhilton665/tanzania_2006/digital_safari.htm#accessories
and scroll UP four paragraphs to 'You may be wondering' for the text
.... the gifs show a great lens, the 500 f/4 L IS (the best lens I own),
compared to the 100-400, with a red mark showing where the 1.6x sensor
edge-of-frame would be located ...

In case you're wondering how an MTF chart translates into real-world
images, with the 100-400 L IS at 400 mm I find the corner light
fall-off is acceptable wide open (f/5.6) with a 10D (1.6x crop), but
with a 1.3x crop like the Canon 1D Mark II I needed to stop down to f/8
and for the full frame 1Ds I needed to stop down to f/11 to get
acceptable (to me ... YMMV) lack of light fall-off in the corners, at
least when viewing the RAW files. The conversions to tiff seem to tone
this down a bit, especially if you use Photoshop CSRAW and apply the
vignetting filter.

As for the 24-105, when I got it I wanted to see what aperture I needed
at 24, 50, 70 and 105 mm for acceptable vignetting with my 1Ds (full
frame) so I ran a bunch of tests, which I had completely forgotten
about until this thread I was in a hurry because I was leaving for
Africa a couple of days after I got the lens (which performed well in
Africa, btw ... the IS and 4:1 zoom range are very useful when shooting
from a vehicle).

Anyway, the MTF curves for wide open 24 mm are pretty crappy so I think
my tests quickly showed me to use it at f/8 or smaller apertures with
the 1Ds ... here is a screen dump of two RAW files at 24 mm, one at
f/11 and one at f/4 showing how the RAW preview in Capture One displays
the light-fall off (f/8 was pretty good too) ... so it's OK at 24 mm
once you stop down a bit, but unacceptable to me wide open, as
predicted by the MTF curve ... of course I can't imagine ever shooting
wide open at 24 mm so to me it's not a hardship ...http://members.aol.com/bhilton665/tests/24mm_vignette.jpg

"Bill Hilton" <> wrote in message
news:...
>> Eatmorepies writes ...
>>
>>I've bought a Canon EF100mm macro lens. Many review sites
>>praised it for sharpness and colour. I have compared it with my
>>24-105mm f4L on extension tubes and it seems to be lacking
>>colour saturation and sharpness
>
> I have both of these lenses and I'm surprised at what you just
> wrote ... the 100 f/2.8 macro is a very good lens.

That's right, but I suspect that the OP used too small an aperture
hoping to preserve some DOF.

This is an example of the shallow DOF at f/5.6 (handheld 1/400 sec at
ISO 200, only daylight) of this fly as it was scoring some dove poop:
<http://www.xs4all.nl/~bvdwolf/temp/2924_CommonHouseFly-T.jpg>

The insets are at 100% zoom and the yellow bits on the poop (if you
want to know) are clumps of spruce pollen. The total DOF was a very
small fraction (!) of a millimetre, and since the focal plane ran
almost exactly between the eyes, most of the facets are OOF.

Bill Hilton wrote:
>>> I wrote ...
>>>
>>> Jeez, the curves for the 24-105 at f/4 are awful! As an owner of the
>>> lens I wish I had never seen these
>
>> Eatmorepies wrote ...
>>
>> Interesting that you report that the L lens at f4 has poor curves. I find it
>> to be excellent on my 350D - am I going to be disappointed when I summon
>> up the courage to lash out for a full frame digital body?
>
> Anyway, the MTF curves for wide open 24 mm are pretty crappy so I think
> my tests quickly showed me to use it at f/8 or smaller apertures with
> the 1Ds ... here is a screen dump of two RAW files at 24 mm, one at
> f/11 and one at f/4 showing how the RAW preview in Capture One displays
> the light-fall off (f/8 was pretty good too) ... so it's OK at 24 mm
> once you stop down a bit, but unacceptable to me wide open, as
> predicted by the MTF curve ... of course I can't imagine ever shooting
> wide open at 24 mm so to me it's not a hardship ...
> http://members.aol.com/bhilton665/tests/24mm_vignette.jpg
>

Thanks for 'splanations. I have the 24-105 [on 20D] and it's become my
walkabout. Since I shoot lots of sports, and induhvidgil peeple, the
vignetting hasn't been a problem for me.... although I am sure to think
about it more! Actually, don't use it for sports except when I am
carrying two cameras; the 70-200 is far more useful, with and without a
1.4x.

Share This Page

Welcome to Velocity Reviews!

Welcome to the Velocity Reviews, the place to come for the latest tech news and reviews.

Please join our friendly community by clicking the button below - it only takes a few seconds and is totally free. You'll be able to chat with other enthusiasts and get tech help from other members.
Sign up now!